Systems and methods for delivering an intravascular device to the mitral annulus

ABSTRACT

The present disclosure describes devices, systems, and methods for intravascularly delivering an implantable device at the mitral annulus. A delivery system includes a delivery member coupled to a handle assembly and extending distally from the handle assembly. The intravascular device is attached at the distal end of the delivery member, and is housed within a distal piece of an outer sheath. A steering catheter is nested within the outer sheath to bend the delivery member into position. A delivery catheter is configured to advance the intravascular device relative to the outer sheath, and a suture catheter includes sutures/tethers which may be coupled to the intravascular device prior to deployment.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority to: U.S. ProvisionalPatent Application Ser. No. 62/368,683, filed on Jul. 29, 2016 andtitled “Intravascular Device Delivery Sheath”; U.S. Provisional PatentApplication Ser. No. 62/368,695, filed on Jul. 29, 2016 and titled“Threaded Coil”; U.S. Provisional Patent Application Ser. No.62/368,702, filed on Jul. 29, 2016 and titled “Combination SteerableCatheter and Systems”; U.S. Provisional Patent Application Ser. No.62/368,711, filed on Jul. 29, 2016, and titled “Hypotube ReinforcedIntravascular Device Delivery Systems and Methods”; U.S. ProvisionalPatent Application Ser. No. 62/380,246, filed on Aug. 26, 2016 andtitled “Rotational Fixation of Catheters”; U.S. Provisional PatentApplication Ser. No. 62/380,795, filed Aug. 29, 2016 and titled “Systemsand Methods for Loading and Deploying an Intravascular Device”; U.S.Provisional Patent Application Ser. No. 62/380,799, filed Aug. 29, 2016and titled “Moveable Guidewire Lumen”; U.S. Provisional PatentApplication Ser. No. 62/380,862, filed Aug. 29, 2016 and titled “Methodsof Steering and Delivery of Intravascular Devices”; U.S. ProvisionalPatent Application Ser. No. 62/380,873, filed on Aug. 29, 2016 andtitled “Multilumen Catheter”; U.S. Provisional Patent Application Ser.No. 62/380,888, filed Aug. 29, 2016 and titled “Methods, Systems, andDevices for Sealing and Flushing a Delivery System”; U.S. ProvisionalPatent Application Ser. No. 62/404,511, filed Oct. 5, 2016 and titled“Systems and Methods for Loading and Deploying an Intravascular Device”;U.S. Provisional Patent Application Ser. No. 62/422,426, filed on Nov.15, 2016 and titled “Delivery Catheter Distal Cap”; U.S. ProvisionalPatent Application Ser. No. 62/430,143, filed on Dec. 5, 2016 and titled“Intravascular Device Delivery Sheath”; U.S. Provisional PatentApplication Ser. No. 62/430,149, filed on Dec. 5, 2016 and titled“Systems and Methods for Loading and Deploying an Intravascular Device”;U.S. Provisional Patent Application Ser. No. 62/436,887, filed Dec. 20,2016 and titled “Mechanical Interlock for Catheters”; U.S. ProvisionalPatent Application Ser. No. 62/436,913, filed on Dec. 20, 2016 andtitled “Methods of Steering and Delivery of Intravascular Devices”; U.S.Provisional Patent Application Ser. No. 62/436,918, filed Dec. 20, 2016and titled “Moveable Guidewire Lumen”; and U.S. Provisional PatentApplication Ser. No. 62/436,926, filed Dec. 20, 2016 and titled“Methods, Systems, and Devices for Sealing and Flushing a DeliverySystem,” the disclosures of which are incorporated herein by referencesin their entireties.

This application also claims the benefit of and priority to: U.S.Provisional Patent Application Ser. No. 62/436,985, filed on Dec. 20,2016 and titled “Systems and Methods for Loading and Deploying anIntravascular Device”; U.S. Provisional Patent Application Ser. No.62/436,922, filed Dec. 20, 2016 and titled “Systems and Methods forLoading and Deploying an Intravascular Device”; and U.S. ProvisionalPatent Application Ser. No. 62/462,776, filed on Feb. 23, 2017 andtitled “Systems and Methods for Loading and Deploying an IntravascularDevice.”

BACKGROUND 1. Field of the Invention

The present disclosure generally relates to an implantable cardiacdevice. In particular, this disclosure describes devices, systems, andmethods for delivering an intravascular device to targeted anatomywithin the heart such as at the mitral annulus.

2. The Relevant Technology

Intravascular medical procedures allow the performance of therapeutictreatments in a variety of locations within a patient's body whilerequiring only relatively small access incisions. An intravascularprocedure may, for example, eliminate the need for open-heart surgery,reducing risks, costs, and time associated with an open-heart procedure.The intravascular procedure also enables faster recovery times withlower associated costs and risks of complication. An example of anintravascular procedure that significantly reduces procedure andrecovery time and cost over conventional open surgery is a heart valvereplacement or repair procedure in which an artificial valve or valverepair device is guided to the heart through the patient's vasculature.For example, a catheter is inserted into the patient's vasculature anddirected to the inferior vena cava. The catheter is then urged throughthe inferior vena cava toward the heart by applying force longitudinallyto the catheter. Upon entering the heart from the inferior vena cava,the catheter enters the right atrium. The distal end of the catheter maybe deflected by one or more deflecting mechanisms, which can be achievedby tension cable, or other mechanisms positioned inside the catheter.Precise control of the distal end of the catheter allows for morereliable and faster positioning of a medical device and/or implant andother improvements in the procedures.

An intravascularly delivered device needs to be placed precisely toensure a correct positioning of the medical device, which is essentialfor its functionality, as the device may be difficult to repositionafter the device is fully deployed from the delivery system.Additionally, the ability to recapture a partially deployed device isdesirable in the event that the distal end of the catheter movesrelative to the target location and compromises the precise positioningof the device.

BRIEF SUMMARY

The present disclosure describes devices, systems, and methods forintravascularly delivering an intravascular device to a targeted cardiacvalve. In one embodiment, a delivery system for intravascularlydelivering an intravascular device to a targeted cardiac valve includesa handle assembly and an elongated delivery member. The delivery memberhas a proximal end and a distal end. The proximal end of the deliverymember is coupled to the handle assembly and the delivery member extendsdistally from the handle assembly to its distal end. The delivery memberis configured to detachably couple to an implantable intravasculardevice at its distal end. The delivery member also includes an outersheath having a cover configured to constrain and/or hold theintravascular device in a pre-deployed configuration, a steeringcomponent configured to curve the delivery member in a compound curvethat enables intravascular delivery of the delivery member to thetargeted cardiac valve, a delivery catheter configured to longitudinallytranslate the intravascular device relative to the outer sheath, and asuture catheter having one or more tethers configured to detachablycouple to a proximal section of the intravascular device. The suturecatheter is longitudinally translatable relative to the deliverycatheter to enable adjustment of tension in the one or more tethers.

In some embodiments, the steering component is a steering catheternested within the outer sheath. The steering catheter may include aplurality of tension cables and corresponding tension cable lumen, thetension cables providing for steering of the steering catheter byadjusting tension in the tension cables. The steering catheter may beformed as a hypotube, the hypotube having a cut pattern that increasesthe flexibility of the hypotube relative to an uncut section ofhypotube. The steering catheter may include a plurality ofmicrofabricated cuts along at least a proximal section of the distalpiece, the microfabricated cuts being configured to provide bending in asingle plane.

In some embodiments, the outer sheath includes a coil and a braidedsleeve. The coil of the outer sheath may be formed from a coil wirehaving a “D” shaped cross section to provide a rounded inner surface.The outer sheath may include a fluid impermeable flexible polymer coverdisposed over the coil and braided sleeve. In some embodiments, thedistal piece of the outer sheath is rotationally decoupled from theremainder of the outer sheath. In some embodiments, the deliverycatheter includes a compression coil at least at a distal section.

In some embodiments, the delivery system is supported by a fixture. Thefixture includes a plurality of supports to support the outer sheath, asteering catheter handle, a delivery catheter holder, and a suturecatheter holder. The fixture also includes one or more adjustablecontrols which enable movement of different components of the deliverymember relative to other components of the delivery member. In someembodiments, the fixture includes a delivery device adjustor forlongitudinally translating the entire delivery device relative to abase, an outer sheath adjustor for translating the outer sheath relativeto other components of the delivery member, and a deployment adjustorfor translating the delivery catheter, outer sheath, and suture catheterrelative to the steering catheter. In some embodiments, the handleassembly includes a delivery catheter holder, a suture catheter holder,and a suture catheter adjustor, the suture catheter adjustor beingcoupled to the delivery catheter holder, and the suture catheter holderincluding threads which engage with corresponding threads of the suturecatheter adjustor such that rotation of the suture catheter adjustortranslates the suture catheter holder relative to the delivery catheterholder

Additional features and advantages will be set forth in part in thedescription that follows, and in part will be obvious from thedescription, or may be learned by practice of the embodiments disclosedherein. The objects and advantages of the embodiments disclosed hereinwill be realized and attained by means of the elements and combinationsparticularly pointed out in the appended claims. It is to be understoodthat both the foregoing brief summary and the following detaileddescription are exemplary and explanatory only and are not restrictiveof the embodiments disclosed herein or as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe various features and concepts of the presentdisclosure, a more particular description of certain subject matter willbe rendered by reference to specific embodiments which are illustratedin the appended drawings. Understanding that these figures depict justsome example embodiments and are not to be considered to be limiting inscope, various embodiments will be described and explained withadditional specificity and detail through the use of the accompanyingdrawings in which:

FIG. 1 illustrates a delivery system configured for delivering,positioning, and deploying an intravascular device, the delivery systemincluding a handle assembly coupled to a delivery member;

FIG. 2 illustrates a cross-section of the delivery member, showingvarious nested components of the delivery member, including an outersheath, a steering catheter, a delivery catheter, a suture catheter, anda guidewire tube;

FIG. 3 illustrates an exemplary approach for delivering an intravasculardevice to the mitral annulus;

FIG. 4 illustrates an embodiment of a fixture configured for supportingthe delivery system, the fixture including a stabilizer and a base;

FIGS. 5A and 5B illustrate operation of the handle assembly to translatethe outer sheath of the delivery member relative to other components ofthe delivery member;

FIGS. 6A and 6B illustrate operation of the handle assembly to translatethe outer sheath, the delivery catheter, and the suture catheterrelative to the steering catheter of the delivery member;

FIGS. 7A and 7B illustrate operation of the handle assembly to translatethe suture catheter relative to the delivery catheter;

FIGS. 8A and 8B illustrate operation of the handle assembly to translatethe guidewire tube relative to the suture catheter;

FIG. 9 illustrates the outer sheath, showing various sections that maybe formed in the outer sheath;

FIG. 10 is a cross-sectional view of FIG. 9;

FIG. 11A is a partial cut-away view of an intermediate portion of thedelivery sheath;

FIG. 11B is a side view of the coil of the intermediate portion of thesheath shown in FIG. 11A;

FIG. 11C is a cross-sectional view of one exemplary configuration of awire for forming the coil of FIG. 11B;

FIG. 12 is a cross-sectional view showing swivel connections between adistal piece and the delivery sheath and between the delivery sheath anda portion of the fixture;

FIGS. 13 and 14 are cross-sectional views of an alternate embodiment ofa swivel connection between the delivery sheath and the fixture;

FIG. 15 illustrates the steering catheter, showing various features andsections that may be formed in the steering catheter;

FIG. 16 illustrates the steering catheter after forming a compound curveshape to enable proper positioning of the delivery member relative tothe mitral annulus;

FIG. 17 illustrates a cross-sectional view of the steering catheter,showing lumens for routing tension cables through the steering catheter;

FIG. 18 illustrates a distal steering ring configured for positioning atthe distal end of the steering catheter;

FIG. 19A illustrates various cut patterns which may be utilized in theouter sheath and/or steering catheter to provide flexibility and/orpreferential bending;

FIG. 19B illustrates bending of the steering catheter, showing featuresof the cut patterns which enable the bending;

FIG. 20 illustrates a detailed view of the delivery catheter;

FIGS. 21A and 21B illustrate exemplary embodiments of a distal tip;

FIGS. 22A through 22E illustrate an exemplary delivery procedure forpositioning the distal end of the delivery member at the mitral annulus;

FIG. 23A depicts a path generally taken by a conventional deliverycatheter through the right atrium of the heart and through theintra-atrial septum;

FIG. 23B depicts an improved path for the delivery member by use ofvarious cut patterns in different sections of the delivery member; and

FIGS. 24A and 24B illustrate a “diving down” procedure for positioningthe delivery member through the mitral valve annulus.

DETAILED DESCRIPTION Delivery System Overview

The present disclosure is directed to devices, systems, and methods fordelivering an implantable intravascular device to targeted intravascularanatomy, including a targeted cardiac valve. Suitable intravasculardevices that may be utilized in conjunction with the delivery systemembodiments described herein may include valve repair devices,annuloplasty devices, valve clip devices, artificial heart valvedevices, and other interventional devices.

FIG. 1 illustrates an embodiment of a delivery system 190. As shown, thedelivery system 190 includes a handle assembly 130 and an elongateddelivery member 70 (also referred to herein as simply the elongatedmember or the delivery member). The delivery member 70 is coupled to thehandle assembly 130 and extends distally from the handle assembly 130.The delivery member 70 includes a plurality of catheter and/or hypotubemembers which provide different functionality during operation of thedelivery system 190 to enable effective delivery and deployment of anintravascular device.

The proximal end of an outer sheath 82 (also referred to herein asdelivery sheath 82) is coupled to an end ring 131, and the outer sheath82 extends to a distal end where it is coupled to a distal piece 84. Thedistal piece 84 functions to house an intravascular device in acompressed, pre-deployed state during intravascular delivery of thedevice to the targeted cardiac site. A steering catheter handle 132 isdisposed proximal of the end ring 131. The proximal end of a steeringcatheter 80 is coupled to the steering catheter handle 132, and thesteering catheter 82 extends distally from the steering catheter handle132 into the outer sheath 82. The steering catheter handle 132 includesone or more controls 134 which are operatively coupled to the steeringcatheter so that manipulation of the controls 134 adjusts the curvatureof the steering catheter 80. Because the steering catheter 80 is nestedwithin the outer sheath 82, curving of the steering catheter 80 causescorresponding curving/steering in the outer sheath 82. The illustratedembodiment of the delivery member 70 includes additional componentswhich are not visible in the view of FIG. 1 but may be seen in thecross-sectional view of FIG. 2.

FIG. 2 illustrates a cross-sectional view of the delivery member 70taken along the cross-section line 2-2. As shown, the steering catheter80 is disposed within the outer sheath 82. A delivery catheter 78 isdisposed within the steering catheter 80. A suture catheter 72 isdisposed within the delivery catheter 78, and a guidewire tube 86 isdisposed within the suture catheter 72. The guidewire tube 86 isconfigured for receiving a guidewire 87. Additional structural detailsand related functionality of these components will be described in moredetail below. Although the particular nested configuration shown in FIG.2 represents one preferred embodiment, alternative embodiments mayinclude a different concentric arrangement of constituent parts. Forexample, some embodiments may configure the outermost member withsteering functionality, some embodiments may include more than onecatheter with steering functionality, some embodiments may trade theradial positions of the suture catheter 72 and delivery catheter 78,etcetera.

The steering catheter 80 includes a plurality of lumens 81 extendingthrough the length of the steering catheter 80. As explained in moredetail below, the lumens 81 may be configured for receiving tensioncables which extend between the controls 134 and the distal end of thesteering catheter 80. One or more tension cables may additionally oralternatively be coupled to intermediate sections of the steeringcatheter 80. Manipulation of the controls 134 therefore adjusts tensionin the tension cables to increase or decrease curvature of the steeringcatheter 80 at various positions. Although the controls 134 are shownhere as knobs, alternative embodiments may additionally or alternativelyinclude one or more buttons, sliders, ratcheting mechanisms, or othersuitable controls capable of adjusting tension to provide steering.Illustrative structures that can be used as part of the steeringcatheter handle 132 and or steering catheter 80 are described in U.S.Pat. No. 7,736,388, the disclosure of which is incorporated herein bythis reference.

Referring again to FIG. 1, a delivery catheter holder 136 is disposedproximal of the steering catheter handle 132. Although not visible inthe view of FIG. 1, the proximal end of the delivery catheter 78 iscoupled to the delivery catheter holder 136. The delivery catheter 78extends distally away from the delivery catheter holder 136 and into thesteering catheter 80. A suture catheter holder 138 is disposed proximalof the delivery catheter holder 136. The suture catheter 72 may becoupled to the suture catheter holder 138 so that translation of thesuture catheter holder 138 corresponds to movement of the suturecatheter 72. For example, the suture catheter 72 may be selectivelylocked relative to the suture catheter holder 138 through a set screw,clamp, or other selective holding mechanism. The suture catheter 72extends distally away from the suture catheter holder 138 and into thedelivery catheter 78.

An alignment ring 137 and alignment rods 142 provide structural supportfor maintaining proper alignment of the delivery catheter holder 136 andsuture catheter holder 138, which thereby functions to maintain coaxialalignment of the delivery catheter 78 and suture catheter 72. A suturecatheter control 139 is coupled to the alignment ring 137 and isoperatively coupled to the suture catheter holder 138. Manipulation ofthe suture catheter control 139 adjusts the relative positioning of thedelivery catheter holder 136 and suture catheter holder 138. In theillustrated embodiment, the suture catheter control 139 operates throughthreaded engagement with the suture catheter holder 138, such thatrotation of the suture catheter control 139 translates the suturecatheter holder 138 relative to the control 139 and therefore relativeto the delivery catheter holder 136. Alternative embodiments mayadditionally or alternatively include one or more of a slider and railassembly, a ratcheting mechanism, or other suitable means of linearadjustment.

A second set of alignment rods 142 extend proximally from the suturecatheter holder 138 and to a suture catheter cap 143. The suturecatheter 72 may extend proximally to and be attached to the suturecatheter cap 143. By decoupling the suture catheter 72 from the suturecatheter holder 138, a user may advance and retract the suture catheter72 by sliding/translating the suture catheter cap 143 along thealignment rods 142. The guidewire tube 86 extends distally through thealignment cap 143 and into the suture catheter 72 at the suture catheterholder 138. The guidewire tube 86 extends to the distal end of thedelivery member 70 where it is attached to a distal tip 88. The distaltip 88 is preferably formed from a flexible polymer material andprovides an angled, atraumatic shape which assists in passing thedelivery member 70 across the inter-atrial septum to the mitral annulus,which is required in a typical intravascular approach such as atransfemoral approach.

The guidewire tube 86 may be selectively translatable relative to thesuture catheter cap 143, so that the guidewire tube 86 and distal tip 88may be linearly translated relative to the suture catheter 72. In theillustrated embodiment, the guidewire tube 86 is coupled to a guidewiretube handle 140. The guidewire tube 86 may be selectively locked inlongitudinal position relative to the suture catheter holder 138 and/orsuture catheter cap 143, such as through a set screw, clamp, or otherselective fastener. For example, such a fastening structure may beassociated with the suture catheter cap 143.

When the guidewire tube 86 is linearly locked to the suture catheter cap143, the guidewire tube 86 will longitudinally translate with thedelivery catheter handle 138 and/or suture catheter cap 143. The distaltip 88 and suture catheter 72 will thus move together. When unlocked,the guidewire tube 86 (and likewise the distal tip 88) may be movedrelative to the suture catheter 72. As described in more detail below,the ability to retract the distal tip 88 relative to the suture catheter72 reduces the risk that the distal tip 88 will become overextendedduring deployment, where it could become tangled in chordae tendineaeand/or cause injury to cardiac tissue.

The illustrated suture catheter holder 138 also includes a set oftensioner posts 144. In some embodiments, sutures may extend from thedistal end of the suture catheter 72 to the tensioner posts 144. Thesutures may be wrapped around respective tensioner posts 144 such thatscrewing/unscrewing of the tensioner posts 144 adjusts tension of thecoupled sutures. However, in other embodiments, sutures do not passentirely to the proximal handle assembly 130 and the tensioner posts 144may be omitted.

FIG. 3 illustrates a schematic representation of a patient's heart and adelivery procedure that may be conducted using the illustrated deliverysystem 190. The delivery member 70 may be inserted into the patient'svasculature (e.g., through a transfemoral approach) and directed to theinferior vena cava 150. The delivery member 70 is passed through theinferior vena cava 150 toward the heart. Upon entering the heart fromthe inferior vena cava 150, the delivery member 70 enters the rightatrium 152. For mitral valve related procedures, the delivery member 70must further pass into the left atrium 156 by passing through a puncturein the intra-atrial septum 154.

In other implementations, such as for procedures associated with atricuspid valve, the delivery member 70 may be passed through theinferior vena cava 150 and into the right atrium 152, where it may thenbe positioned and used to perform the procedure related to the tricuspidvalve. As described above, although many of the examples describedherein relate to delivery to the mitral valve, one or more embodimentsmay be utilized in other cardiac procedures, including those involvingthe tricuspid valve.

Although a transfemoral approach for accessing a targeted cardiac valveis one preferred method, it will be understood that the embodimentsdescribed herein may also be utilized where alternative approaches areused. For example, embodiments described herein may be utilized in atransjugular approach, transapical approach, or other suitable approachto the targeted anatomy. For procedures related to the mitral valve ortricuspid valve, delivery of the replacement valve or otherinterventional device is preferably carried out from an atrial aspect(i.e., with the distal end of the delivery member 70 positioned withinthe atrium superior to the targeted valve). The illustrated embodimentsare shown from such an atrial aspect. However, it will be understoodthat the interventional device embodiments described herein may also bedelivered from a ventricular aspect.

In some embodiments, a guidewire 87 is utilized in conjunction with thedelivery member 70. For example, the guidewire 87 (e.g., 0.014 in, 0.018in, 0.035 in) may be routed through the guidewire tube 86 of thedelivery member 70 to the targeted cardiac valve.

Operation of the Handle Assembly

FIG. 4 illustrates the handle assembly 130 positioned on a fixture 176.The fixture 176 includes a stabilizer 160 which supports the handleassembly 130 and provides adjustment of various components of the handleassembly 130. The fixture 176 also includes a base 161 configured tosupport the stabilizer 160 and handle assembly 130, and to provide theability to adjust the position of the entire handle assembly 130. Thebase 161 may include wheels 162 for moving and positioning of theassembly. The base 161 also includes an angular adjuster 164 configuredfor adjusting the angle of the handle assembly 130 by lifting orlowering the upper section of the base 161. The base 161 furtherincludes a slider lock 163. Unlocking of the slider lock 163 allows auser to slide an upper section 191 of the base forward or backwardrelative to a lower section 192 of the base in order to selectivelyadvance or retract the delivery system.

The fixture 176 may also include a base bearing 165 connected to thebase 160 and to a stabilizer adjustor 173. The base bearing 165 allowsthe stabilizer adjustor 173 to rotate but prevents linear movement ofthe stabilizer adjustor 173 relative to the base bearing 165. Thestabilizer adjustor 173 includes threads which engage with correspondingthreads of a proximal support 171 of the stabilizer 160. The proximalsupport 171 is mechanically connected to a steering catheter handlesupport 169 and a distal support 172. Rotation of the stabilizeradjustor 173, as shown by arrow 178, thus causes the entire stabilizer160 to translate relative to the base 161. For example, rotation of thestabilizer adjustor 173 in one direction will advance the stabilizer 160(and handle assembly 130 with it) while rotation in the oppositedirection will retract.

The illustrated fixture 176 is therefore configured to provide dual-modetranslation of the delivery system. For example, manipulation of theslider lock 168 may be utilized for translational adjustments of thedelivery system on a relatively more macro level, while manipulation ofthe stabilizer adjustor 173 may be utilized for finer translationaladjustments on a relatively more micro level. The combination of bothmodes of translation beneficially combines the ability for rapidadjustment across longer translational movements with the ability forfine adjustment where more precise movements are required or preferred.

The stabilizer 160 includes additional components configured to provideadjustment of the different components of the handle assembly 130. Theouter sheath 82 is supported by an outer sheath support 166. The outersheath support 166 is disposed upon a slider block 167. The outer sheathsupport 166 can be selectively translated upon the slider block 167 totranslate the outer sheath 82 relative to the other components of thedelivery member 70. A slider lock 168 can lock the position of the outersheath support 166 upon the slider block 167 to prevent translation viasliding.

The steering catheter handle 132 is supported by the steering catheterhandle support 169, and the delivery catheter holder 136 is supported bya delivery catheter support 170. The proximal support 171 supports thesuture catheter holder 138. An outer sheath adjustor 174 and adeployment adjustor 175 enable additional operation of the deliverydevice, as described in more detail below. As shown, connecting rods 177are attached to the delivery catheter support 170, pass slidably throughthe steering catheter handle support 169 and the distal support 172, andattach to the sliding block 167. Translation of the delivery cathetersupport 170 may therefore be coupled to translation of the outer sheathsupport 166 in some circumstances.

FIGS. 5A and 5B illustrate in greater detail operation of the handleassembly for translating the outer sheath 82. Sheath movement may beutilized to deploy an intravascular device sheathed at or otherwiseattached to the distal end of the outer sheath 82, or to recapture suchan intravascular device by advancing the outer sheath 82 over thedevice. The illustrated embodiment provides two modes for translatingthe outer sheath 82. The outer sheath adjustor 174 and the slider block167 are coupled to each other with corresponding threads, and rotationof the outer sheath adjustor 174 causes the slider block 167 totranslate. With the slider lock 168 engaged, the outer sheath support166 and outer sheath 82 move with the slider block 167. The slider lock168 may also be disengaged, allowing the outer sheath support 166 andouter sheath 82 to be manually advanced or retracted by sliding relativeto the slider block 167.

As shown by corresponding arrows 180, rotation of the outer sheathadjustor 174 in one direction causes the slider block 167 to advance,and as shown by corresponding arrows 181, rotation of the outer sheathadjustor 174 in the opposite direction causes the slider block 167 toretract. In FIG. 5A, the slider lock 168 is in an engaged position. InFIG. 5B, arrows 182 show disengagement of the slider lock 168 andtranslation of the outer sheath support 166 upon the slider block 167.The dual mode adjustment of the outer sheath 82 beneficially allows auser to make different types of adjustments depending on proceduralcircumstances and/or preferences. For example, a user may make larger,quicker adjustments by unlocking the slider lock 168 and manuallysliding the outer sheath support 166, and may make finer, morecontrolled adjustments by rotation of the outer sheath adjustor 174.

FIGS. 6A and 6B illustrate a deployment adjustment that moves several ofthe delivery member components relative to the steering catheter 80.FIG. 6A illustrates, by arrows 183, rotation of the deployment adjustor175 in a first direction to retract the slider block 167, deploymentcatheter holder 136, and suture catheter holder 138. FIG. 6Billustrates, by arrows 184, rotation of the deployment adjustor 175 in asecond direction to advance the slider block 167, deployment catheterholder 136, and suture catheter holder 138. As explained below, afterthe steering catheter 80 has been curved to orient the delivery member70 with respect to the mitral annulus, the other components of thedelivery member 70 will need to be advanced over the steering catheter80 to move into a proper position for deployment of the intravasculardevice. Holding the steering catheter 80 in place while the othercomponents are advanced allows the compound curve of the steeringcatheter 80 to remain in the desired position.

The deployment adjustor 175 is threadedly engaged with the deliverycatheter support 170. The connecting rods 177 mechanically link thedelivery catheter support 170 to the slider block 167. The connectingrods 177 are able to freely pass through the steering catheter handlesupport 169 without engaging. The delivery catheter holder 136 and thesuture catheter holder 138 are also mechanically linked by way of thealignment ring 137 and suture catheter control 139. Accordingly,rotation of the deployment adjustor 175 causes the delivery catheterholder 136, slider block 167, and suture catheter holder 138 totranslate while the position of the steering catheter handle 132 ismaintained. Translation of the outer sheath support 166 can be assuredby locking to the slider block 167.

FIGS. 7A and 7B illustrate an operation for moving the suture catheterholder 138 relative to the delivery catheter holder 136. FIG. 7A shows,by arrows 185, that rotation of the suture catheter control 139 in afirst direction causes the suture catheter holder 138 to advancerelative to the delivery catheter holder 136. FIG. 7B shows, by arrows186, that rotation of the suture catheter control 139 in a seconddirection causes the suture catheter holder 138 to retract relative tothe delivery catheter holder 136. The threaded engagement of the suturecatheter control 139 to the suture catheter holder 138 allows for finelycontrolled adjustments of the suture catheter position. As explained inmore detail below, sutures of the suture catheter 72 may be coupled toan intravascular device while the device is in a pre-deployed state, andmovement of the suture catheter 72 relative to the delivery catheter 78allows tension of the sutures to be adjusted.

FIGS. 8A and 8B illustrate an operation for moving the guidewire tube 86and guidewire tube holder 140 relative to the other components of thedelivery member 70. FIG. 8A shows, by arrows 187, retraction of theguidewire tube holder 140 and corresponding retraction of the distal tip88. FIG. 8B shows, by arrows 188 advancement of the guidewire tubeholder 140 and corresponding advancement of the distal tip 88. Theability to adjust the distal tip 88 can lower the risk that the distaltip 88 undesirably interferes with chordae tendineae or other cardiacanatomy during deployment procedures. For example, during deployment ofan intravascular device, the suture catheter 72 may be advanced todisengage from the intravascular device. If the distal tip 88 is notretracted relative to the advancing suture catheter 72, the distal tip88 could extend too far into the ventricle where it could catch chordaetendineae and/or impinge against the cardiac wall.

Additional Details of Elongated Member Components

FIGS. 9 and 10 illustrate a portion of the distal end of the outersheath 82 and distal piece 84. Distal piece 84 can be made of a steelcylindrical tube having an inner diameter and length sized to receivethe intravascular device, in a collapsed/pre-deployed configuration,within the lumen of distal piece 84. Distal piece 84 can include aplurality of microfabricated cuts (e.g., laser cuts) and a pair ofcontinuous longitudinal spines located on opposite sides so that covercan bend and flex substantially in a single plane. The outer sheath 82can also include a bending portion 434 that can be attached to andlocated proximal to distal piece 84. Bending portion 434 can preferablyhave a sufficient length to surround and extend along that portion ofthe delivery system that is designed bend and reorient, via thesteerable catheter 80, to navigate through a patient's vasculatureand/or heart to a target site for deploying the intravascular device. Insome embodiments, the bending portion 434 can include a cable tube orcoil 436 surrounded by a braided structure 438 (sometimes collectivelyreferred to as the “coil/braid portion 436/438”) as shown in FIG. 11A.

FIG. 11A is a perspective cutaway view of the sheath 82. As shown, thesheath 82 may have an inner cable tube or coil 436 and an outer braidedsleeve or structure 438. Coil 436 can be made of or include a resilientcoil material. For example, the coil material may be stainless steel,nickel titanium (e.g., Nitinol), other metal alloy, a thermoplastic,other polymers such as PEEK, ceramics, carbon tubing, glass, orcombinations thereof. In at least one embodiment, coil 436 can be astainless steel coil that has a droop value of 11:1 or higher. Coil 436can be sized relative to the braided structure 438 such that the coil436 has an outer diameter (“OD”) in a relaxed state that issubstantially the same as an inner diameter (“ID”) of braided structure438 in a relaxed state.

In preferred embodiments, the coil 436 has an inner surface sufficientlysmooth to allow the outer sheath 82 to effectively move over thesteering catheter 80 and/or delivery catheter 78. For example, as shownin FIG. 11B, the wire forming the coil 436 may have a “D”cross-sectional shape or other rounded shape such that the inward facingside is curved to minimize interference with other componentstranslating within the coil 436.

FIG. 11C shows another view of the coil 436 showing a coil end 437(which may represent a proximal end and/or a distal end). As shown, thecoil end 437 is formed with a fully closed circumference. This allowsthe coil end 437 to more readily welded, adhered, or otherwise attachedto a connecting ring or hypotube section of the elongated member 70. Forexample, the closed coil construction of the coil end 437 allows a laserweld to cover the full 360-degree circumference of the coil end 437.

In some embodiments, braided sleeve 438 may include a plurality ofthreads or fibers that are woven together. For example, braided sleeve438 may include a plurality of threads that extend at an angle to oneanother and are woven together in a repeating pattern. The plurality ofthreads may be woven in a diamond two wire two-under-two, over-twopattern; a half-load single wire over-one, one-under pattern; afull-load single wire over-two, under-two pattern; other alternatingwoven patterns; or combinations thereof. In other embodiments, braidedsleeve 438 may include a single thread routed substantially straightlongitudinally through the plurality of threads.

The threads may be round threads, elliptical threads, or flat threads.The threads may be made of or include a variety of reinforcementmaterials, such as, metals, metal alloys, thermoplastics, otherpolymers, ceramics, glasses or combinations thereof. In someembodiments, the reinforcement material or materials may have a greaterelastic modulus than the body material. For example, a braided sleevemay include a mixture of threads with different properties, such asstainless steel threads woven with polymer threads. In at least oneembodiment, braided sleeve 438 may include a plurality of 304 stainlesssteel wires woven in a diamond pattern. Such an embodiment of a braidedsleeve may include between 16 and 72 threads of stainless steel. Forexample, braided sleeve 438 may include 24 strands, with each strandconsisting of four wires.

Coil 436 and braided sleeve 438 may be longitudinally fixed to oneanother at or near a proximal end of the outer sheath 82 and at or nearthe distal end of the outer sheath 82. In some embodiments, the braidedsleeve 438 may be welded or soldered to the coil 436 at a proximal endand at a distal end of the outer sheath 82. In other embodiments, thebraided sleeve 438 may be fixed to the coil 436 with an adhesive at aproximal end and a distal end of the outer sheath 82. In yet otherembodiments, the braided sleeve 438 may be fixed to the coil 436 via anintermediate element (e.g., an annular end cap) at a proximal end and adistal end of the outer sheath 82. In yet other embodiments, braidedsleeve 438 and coil 436 may be longitudinally fixed relative to oneanother at one or more points between a proximal end and a distal end ofthe outer sheath 82. For example, braided sleeve 438 and the coil 436may be longitudinally fixed relative to one another at a centerpoint.

Referring again to FIGS. 9 and 10, attached to the proximal end ofbending portion 434 is a cut hypotube 442 that extends from bendingportion 434 to the proximal end of the sheath 82. Hypotube 442 caninclude a plurality of slits and at least one longitudinally continuousspine that can preferably be continuous and uninterrupted along alongitudinal length of, and located at a fixed angular location on,hypotube 442.

In some embodiments, the longitudinally continuous spine of hypotube 442may allow the sheath 82 to transmit tension force applied at a proximalend of the sheath 82 to a distal end of the sheath 82 withoutsubstantial elongation of the sheath 82. In other embodiments, thelongitudinally continuous spine hypotube 442 may allow the sheath 82 totransmit compression force applied at a proximal end to the distal endwithout substantial shortening of the sheath 82. For example, someembodiments of a sheath may exhibit a change in a longitudinal length ofless than 30% during application of a compression force of 40 pounds(177.9 Newtons) or greater and/or application of a tension force of 40pounds (177.9 Newtons) or greater.

In other examples, some embodiments of a sheath may exhibit a change ina longitudinal length of less than 5% during application of acompression force of 40 pounds (177.9 Newtons) or greater and/or atension force of 40 pounds (177.9 Newtons) or greater. In yet otherexamples, some embodiments may exhibit a change in a longitudinal lengthof less than 2% during application of a compression force of 40 pounds(177.9 Newtons) or greater and/or a tension force of 40 pounds (177.9Newtons) or greater.

In some embodiments, the outer sheath 82 may transmit tension forcewithout substantial change to the longitudinal length of the deliverysheath and may foreshorten by 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%,75%, 100%, 150%, 200%, 250%, 300%, 350%, 400% or any value therebetweenduring compression. In at least one embodiment, the coil 436 maycompress by a percentage of the initial longitudinal length of thesheath 82 before the coils contact one another and the coil 436transmits compression forces along the longitudinal length thereof. Forexample, the coil rings may have an initial (i.e., non-stressed) spacingof between 0.1 mm and 5.0 mm, between 1 mm and 4 mm, between 2 mm to 3mm, or any values therebetween to provide a bending radius to navigatethe anatomy toward and into a patient's heart.

In such embodiments, it can be desirable for the bending portion 434 ofdelivery catheter to remain liquid tight. To seal the bending portion434, a flexible, fluid impermeable covering can be provided over thecoil/braid portion 436/438, extending from the distal piece 84 to alocation proximal the coil/braid portion 436/438. For example, thedelivery sheath 82 can also include a thin walled flexible cover 440that extends from the distal piece 84 to the hypotube 442. Flexiblecover 440 can be bonded at each end to the underlying structure, usingone of a variety of different adhesives, thermal adhesives, UV bondedadhesive, or other techniques. Flexible cover 440 can be fabricated fromPelathane 80A, Tecoflex 72A, Texin 70A, Chronoflex 45D, or othersuitable flexible material. Flexible cover 440 can also be coated withhydrophilic coating. The wall thickness of flexible cover 440 could bebetween 0.001″ to 0.006″ and preferably between 0.002″ to 0.004″, andcould have a diameter smaller than an outer diameter of the coil/braidportion 436/438.

Flexible cover 440 can be bonded at its distal end to a proximal endportion of distal piece 84 and can be bonded at is proximal end to adistal end portion of hypotube 442. An intermediate portion of flexiblecover 440, including that portion that extends over the flexiblecoil/braid portion 436/438, is not bonded to flexible coil/braid portion436/438, but rather can preferably be press fit or otherwise able tomove relative to, and stretch over, flexible coil/braid portion 436/438.Flexible cover 440 can preferably be made of a material with someelasticity and can be attached at opposing ends to underlying structurein a way that it is stretched and normally retains some tension, whichcan help avoid wrinkles forming in flexible cover 440 when the deliverysheath 82 is bent or otherwise flexed. When flexible cover 440 isstretched onto the coil/braid portion 436/438 during fabrication,flexible cover 440 can foreshorten by up to 20%, but can easily stretchso as not to impair the flexibility of coil/braid portion 436/438.

During delivery, coil/braid portion 436/438 can be stretched to thepoint where the braided structure 438 locks down on the coil 436 and cantransmit high tension forces that may be needed to retract the outersheath and distal piece 84 from the intravascular device. Conversely, ifrecapture of the intravascular device should become necessary, havingthe coil/braid portion 436/438 under a certain amount of compression insome circumstances can also provide an advantage. The stretching offlexible cover 440 also accommodates these relative movements of coil436 and braided structure 438 within coil/braid portion 436/438.

To facilitate fabrication, a mandrel can be disposed within the lumen ofthe delivery sheath 82, thereby stiffening delivery sheath 82, so thatflexible cover 440 can be stretched and/or rolled over coil/braidportion 436/438, and then the opposing ends of flexible cover 440 can besealed to the underlying structure.

Referring again to FIG. 10, delivery sheath 82 can also be coupled todistal piece 84 via a swivel connection, generally indicated at 450. Toovercome the challenging forces that can develop during insertion of arelatively large delivery catheter into the vasculature of a patient,swivel connection 450 allows rotation of delivery sheath 82 by a fewdegrees, back and forth (i.e., alternating between clockwise rotationand counter-clockwise rotation) while at the same time moving thedelivery system 400 in a generally longitudinal direction. Thisrotational motion (during simultaneous longitudinal translation) helpsto overcome some of the longitudinal forces that may resist insertion ofdelivery sheath 82 through a patient's vasculature.

However, in some embodiments the intravascular device can be positionedwithin and covered by the distal piece 84 and can also be connected tothe delivery catheter within the delivery system. Therefore, it might bedesirable for an intermediate portion of the delivery sheath 82 (such asbending portion 434 and hypotube 442) to be free to swivel relative tothe intravascular device and distal piece 84 while maintaining theintravascular device in stable and proper alignment with the deliverycatheter 76.

To facilitate this, the distal piece 84 can be rotationally decoupledfrom distal end of the delivery sheath 82 by providing a swivelconnection between a proximal end portion of distal piece 84 and thedistal end portion of delivery sheath 82. In the embodiment shown inFIG. 10, a first swivel connection 450 can be formed between theproximal end of distal piece 84 and the distal end of bending portion434. For example, first swivel connection 450 can consist of an enlargedannular flange 452 welded to the distal end of the coil/braided sleeve436/438, and flange 452 can be interposed between a pair of annularrings or ridges 454 a and 454 b formed on an inner surface of distalpiece 84 at its proximal end. These structures cooperate to rotationallydecouple the distal piece 84 from the bending portion 434, but at thesame time maintain coupling between these elements in terms oflongitudinal movement.

While the illustrated embodiment uses cooperating flanges, rings and/orridges, other suitable elements can also be used to accomplish the samefunctions, including, but not limited to rings, welds, detents, or othersuitable structures. The first swivel connection 450 can also includeone or more o-rings or other sealing components (not shown) positionedbetween the cooperating elements of the swivel to provide a fluid-tightswivel connection. A second embodiment of first swivel connection 450 isillustrated in FIG. 12.

Similarly, as further illustrated in FIG. 12, a second swivel connection452 can also be formed at the proximal end of the sheath to rotationallydecouple the delivery sheath 82 from the control fixture 454 (shownschematically only). Second swivel connection 452 can include a pair ofspaced-apart, annular ridges 456 a and 456 b formed on the exteriorsurface and adjacent to the proximal end of hypotube 442. Annular ridges456 a and 456 b form an annular recess 458 between which a complementaryaperture 460 formed in fixture 454 can be positioned. Second swivelconnection 452 can also include one or more o-rings or other sealingcomponents (not shown) positioned between the cooperating elements ofthe swivel to provide a fluid-tight swivel connection.

A second embodiment of second swivel connection 452 is illustrated inFIG. 13. In this embodiment, fixture 454 can provide a two-piece clamp462 a and 462 b that includes an annular recess 464 that receives anannular ring 466 formed on the exterior of hypotube 442 at its proximalend. Ring 466 can easily be welded to the proximal end of hypotube 442.As further shown in FIG. 14, the ring can also have a pin 468 thatextends into a complementary groove 470 formed in clamp 462. Pin 468 andgroove 470 cooperate to limit rotation of ring 466 relative to clamp 462within a predetermined swivel angle range (e.g., between plus and minus15°), but any swivel angle can be accommodated by simply extending orreducing the length of groove 470.

As further illustrated in FIG. 13, an elastic bellow 472 can also beprovided at the proximal end of hypotube 442. Bellow 472 allows a watertight connection, while at the same time accommodating rotationalmovement of hypotube 442. In addition, bellow 472 can stretch orcompress when the delivery sheath 82 is moved longitudinally in a distalor proximal direction, as necessary, during delivery, deployment and/orrelease of the intravascular device. Finally, a standard luer lockconnection 474 can be provided at the proximal end of bellow 472 tofacilitate flushing of the interstitial spaces within delivery sheath 82in preparation for an intervascular procedure.

FIG. 15 illustrates one embodiment of the steering catheter 80 ingreater detail. In the illustrated embodiments, the steering catheter 80includes a proximal section 518, intermediate section 516, and a distalsection 514. A steering ring 510 is connected at the distal end. Adistal cap 512 positioned over the steering ring 510 provide anangled/rounded surface that allows the steering catheter 80 to moreeffectively move and slide against the outer sheath 82 without binding.In this embodiment, the steering catheter 80 is formed as a hypotube.The proximal section 518 may remain uncut, while the intermediatesection 516 and distal section 514 may be cut (e.g., laser cut) toincrease flexibility. Although not shown in this view, a polymer layersurrounds the steering catheter and forms the outer layer.

In some embodiments, the steering catheter 80 is rotationally keyed tothe outer sheath 82. The outer sheath 82 may include cut patterns and/orother features which are arranged to provide particular bendingdirections. In this embodiment, because bending of the outer sheath 82depends upon curving of the steering catheter 80, rotational alignmentof the outer sheath 82 to the steering catheter 80 is beneficial. Thesecomponents may be keyed together using a key and corresponding keywayfeature, slots and corresponding tabs, or other rotational keyingmechanism known in the art. Alternatively, or additionally, alignmentmarkers can be provided at the handle assembly to visually indicatealignment.

To provide effective steering and positioning at the mitral annulus, thedistal section 514 is cut with a pattern which allows a bending radiusof about 15 mm or less (e.g., 5 to 15 mm). The intermediate section 516is cut to allow a bending radius of about 30 to 45 cm. The proximalsection is uncut to provide the steering catheter 80 with sufficientstiffness, torquability, and pushability. The steering catheter 80 maybe sized so that the inner diameter is about 0.15 to 0.20 inches, with awall thickness of about 0.040 to 0.050 inches. As discussed above, thesteering catheter 80 includes a set of tension cables which pass fromthe steering catheter handle to the steering ring 510. Adjusting tensionof the tension cables allows the steering catheter 80 to be curved. Thetension cables have a diameter that allows them to fit within the wallof the outer layer of the steering catheter 80, such as a diameter ofabout 0.01 to 0.02 inches, or about 0.015 to 0.018 inches.

FIG. 16 illustrates an example of a series of compound bends that thesteering catheter 80 may perform during the delivery, repair, recapture,or repositioning of the intravascular device. While accessing the mitralannulus, the steering catheter 80 may be steered in at least two planesof motion. The two planes of motion may be substantially perpendicularto one another. The steering catheter 80 has a first bend 502 with afirst bend angle 503 measured between a first longitudinal axis 506 anda second longitudinal axis 507. In some embodiments, the first bendangle 503 may be in a range having an upper value, a lower value, or anupper and lower value including any of 60°, 65°, 70°, 75°, 80°, 85°,90°, 100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°,155°, 160°, 165°, 170°, or 175°. In one embodiment, the first bend angle503 is in a range of about 90° to 120°, or is about 105°.

The steering catheter 80 has a second bend 504 having a second bendangle 505. The second bend 504 is formed between a third longitudinalaxis 508 and the second longitudinal axis 507. The second bend 504 mayalso have a rotational angle 509 relative to a plane in which the firstlongitudinal axis 506 and the second longitudinal axis 507 lie. In otherwords, the rotational angle 509 is relative to the amount of rotation ofthe third longitudinal axis 508 relative to the direction of the firstbend 502.

The second bend angle 505 may be in a range having an upper value, alower value, or an upper and lower value including any of 60°, 65°, 70°,75°, 80°, 85°, 90°, 95°, 100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°,140°, 145°, 150°, 155°, 160°, 165°, 170°, or 175°, In one embodiment,the second bend angle 505 is in a range of about 80° to 110°, or isabout 90°. The rotational angle 509 may be in a range having an uppervalue, a lower value, or an upper and lower value including any of 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 100°, 110°,120°, 130°, 140°, 150°, or 160°. In one embodiment, the rotational angle509 may be in a range of 45° to 135° or may be about 60°.

FIG. 17 is a cross-sectional view of the outer layer of the steeringcatheter 80, showing a series of lumen 581 for routing of the tensioncables 583. In some embodiments, the lumen 581 are held open withmicro-coils, at least at the distal section 514 where greater bendingtakes place. The micro-coils maintain effective flexibility while alsokeeping the lumen clear and open, while minimizing bowing, for properoperation of the tension cables 583. In some embodiments, a braidmaterial covers the lumen 581 in the intermediate section 516 and/orproximal section 518. In one embodiment, the polymer outer layer is apolyether block amide. The polymer outer layer may be formed to be havegreater flexibility at the distal section 514 than at the intermediateand proximal sections 516, 518. For example, the polymer layer at thedistal section 514 may have a durometer of about 30 to 40D, or about35D, whereas at the intermediate section 516 and/or proximal section 518the polymer layer has a durometer of about 55 to 85D, or about 65 to75D.

FIG. 18 shows the distal steering ring 510. The steering ring 510includes a set of distal holes 514. Each pair of distal holes 514surrounds a saddle feature 512. A tension cable may be routed distallyto the steering ring 510, through one of the distal holes 514, and thenover the adjacent saddle feature 512 and back through the oppositedistal hole 514. The saddle feature 512 has a curved surface on whichthe overlying tension cable rests, which minimizes pinching of thetension cable. The steering ring 510 may also include one or moreproximal holes 516, which can be used for attaching the steering ring510 to the distal end of the steering catheter 80 (via adhesives and/orlaser welding, for example).

FIG. 19A shows various cutting patterns that can be used in differentsections of the steering catheter 80 (and corresponding sections of theouter sheath 82) to produce the desired bends. Each section can includecut patterns that can include one or more slits 556 and/or one or moreisland cuts 558. The slits 556 may transmit longitudinal force along thecatheter and also allow expansion of the catheter when it is deflectedin a direction opposite the slit 556. The island cuts 558 may allowcompression of the catheter when it is deflected in a direction of theisland cuts 558. For example, slits 556 and island cuts 558, whenlocated on opposite sides from one another, may direct preferentialbending of the catheter, as shown by exemplary bend 504 in FIG. 19B.

In one embodiment, illustrated in FIG. 19A, a cutting pattern caninclude five sections or regions 560, 562, 564, 566 and 568, withdifferent cut patterns in each section. Such sections may be arranged asneeded to provide the desired compound curve profile. For example, afirst section 560 can include a plurality of holes radially spaced aboutthe periphery of the catheter. These holes provide flexibility withoutforming a particular bending direction. A second section 562 providesfor bending in a first direction, a third section 564 is similar to thesecond section 562 but with smaller sized and more closely spaced islandcuts 558, a fourth section 564 provides for bending in a seconddirection, and a fifth section 566 includes multiple slits for addingflexibility without forming a particular bending direction. While theisland cuts 558 are depicted as diamond-shaped, the island cuts 558 mayhave one or more other shapes, such as square, rhombohedral, triangular,rectangular, circular, oblong, other elliptical, other polygonal,irregular, or combinations thereof.

FIG. 20 illustrates one embodiment of the delivery catheter 78 ingreater detail. The delivery catheter 78 includes a proximal section 604and a distal section 602. At the proximal end, the delivery catheter 78includes a seal 606 and an o-ring 608 for forming a fluid tight seal atthe delivery catheter holder 136. In the illustrated embodiment, thedistal section 602 is formed as a compression coil. The compression coilprovides the delivery catheter 78 with ability to effectively push theintravascular device through the steering catheter 80 as part ofdeployment. The compression coil also provides good flexibility foradvancing within the compound curve of the steering catheter 80. In thisembodiment, the proximal section 604 is formed as a cut (e.g., lasercut) hypotube.

FIG. 21A illustrates one embodiment of a distal tip 988 having an activeelement 908 to aid in removal of the distal tip 988 in the case that itbecomes caught or tangled in chordae. The illustrated embodimentincludes distal portion 902, a proximal section 904, and a lip 906. Thediameter of the tip at the lip 906 is sized to match an inner diameterof the distal piece so that the lip 906 can be seated within the distalpiece. As shown, the active element 908 may be formed as a thread orspiraled set of grooves. The grooves preferably extend from the proximalend of the tip 988 onto the lip 906. The grooves of the active element908 may have a pitch of about 30 to 60 degrees. The structure of such anactive element allows the tip 988 to be “screwed out” of entangledchordae by rotating the guidewire tube to which the tip 988 isconnected.

The tip 988 may be coupled to the guidewire tube 86 using an adhesive,welding, a friction fit, a threaded connection, and/or other suitableconnection means. FIG. 21B illustrates, in cross-sectional view, oneembodiment where the tip 988 is formed as two separate pieces. Thedistal piece 910 and proximal piece 912 may be fit together at a snapfit feature 914, as shown. Alternatively, the distal piece 910 andproximal piece 912 may include corresponding threads to allow a threadedconnection, and/or the tip 988 may include a cutting ring fitting (e.g.,metal or plastic) configured to deform to hold the separate pieces inposition when the separate pieces are screwed or snapped together. Theguidewire tube 86 may also include a holding ring 916 that the two-piecetip 988 can be positioned around and mechanically interfere with. Theholding ring 916 may also function as a mechanical stopper. The holdingring 916 may also be formed of a radiopaque material. In someembodiments, a pouch or cavity of cyanoacrylate or other suitableadhesive is included in one of the separate pieces, and is positioned tobreak open to release the adhesive when the separate pieces areconnected.

Exemplary Delivery Procedures

FIGS. 22A through 22E illustrate an exemplary approach for deliveringthe intravascular device to the mitral annulus. In some circumstances,the intravascular device, distal piece, and other associated componentsmay be relatively rigid and/or long, which can complicate delivery. FIG.22A illustrates an embodiment of a delivery member 270 and distal piece284 positioned in the right atrium 152 of a heart. A guidewire 287 maybe inserted through the intra-atrial septum and into the left atrium 156of the heart. The intravascular device is then urged longitudinallythrough the intra-atrial septum 154 to the left atrium 156, as shown inFIG. 22B.

FIG. 22B shows the delivery member 270 and positioned in the left atrium156. The distal piece 284 may have a longitudinal length such that thedistal end of the device strikes the wall of the left atrium oppositethe intra-atrial septum 154 if the distal end of the device ispositioned over the mitral annulus 158 before deflecting/curving thedelivery member 270.

In some embodiments, the delivery member 302 is advanced until thedistal tip is positioned just beyond the intra-atrial septum and justinto the left atrium 156. For example, less than 5 mm, less than 4 mm,less than 3 mm, less than 2 mm, or less than 1 mm of the distal piece284 may be located in the left atrium 156. As shown in FIG. 22C, thedistal section of the device may be deflected/curved an amount towardthe mitral annulus 158 by steering the steering catheter toward thetarget location.

After deflecting/curving a first amount, the delivery member 270 may belongitudinally advanced further to position a greater amount of thedistal piece 284 through the septum and into the left atrium, as shownin FIG. 22D. The device may be iteratively deflected/curved and advancedas necessary to achieve the desired position substantially normal to themitral annulus as shown in FIG. 22E, while avoiding hitting against thecardiac wall.

As shown in FIGS. 23A and 23B, the right atrium 152 of a human heartprovides limited space in which to bend or steer a catheter from thedirection in which the inferior vena cava enters the heart to adirection in line with the intra-atrial septum. For longerinterventional devices, it may be more difficult to make the necessarybend within the confines of the right atrium 152. FIG. 23A graphicallydepicts a path generally taken by a conventional delivery catheterthrough the right atrium 152 and through the intra-atrial septum to theleft atrium 156.

To address this issue, the delivery member may be configured to producea first bend at a first location 206 near a distal end 210, while alsoproducing a second bend at a second location 208 proximal the firstlocation 206. This can provide an improved path for the elongateddelivery member, as graphically illustrated in FIG. 23B, that canprovide additional space in which to allow the distal end portion of thecatheter and intravascular device to make the turn within the rightatrium 152. The second bend at the second location 208 can be in adirection substantially opposite to that of the first bend at the firstlocation 206. By so doing, the second bend pushes or “kicks” theelongated delivery member in the opposite direction from the movement ofthe distal tip near the first location 206. This movement urges thedelivery member near the first bend location 206 to move toward the wallof the right atrium 152 and creates more space for the distal tip 210 tobend and penetrate the intra-atrial septum.

FIGS. 24A and 24B illustrate a maneuver for advancing the distal end ofthe delivery member 270 into the mitral annulus 158 after the distalpiece 284 has been properly positioned above the mitral annulus 158 viacurves/bends 220 and 222. As shown, the delivery member 270 is advanceddistally forward through the mitral annulus although the compound curveshape of curves 220 and 222 is maintained. As described above withreference to FIGS. 6A and 6B, this is possible because the outer sheath,distal piece, delivery catheter, suture catheter, and guidewire tube maybe advanced relative to the steering catheter while the steeringcatheter maintains its compound curve shape.

The articles “a,” “an,” and “the” are intended to mean that there areone or more of the elements in the preceding descriptions. The terms“comprising,” “including,” and “having” are intended to be inclusive andmean that there may be additional elements other than the listedelements. Additionally, it should be understood that references to “oneembodiment” or “an embodiment” of the present disclosure are notintended to be interpreted as excluding the existence of additionalembodiments that also incorporate the recited features. Numbers,percentages, ratios, or other values stated herein are intended toinclude that value, and also other values that are “about” or“approximately” the stated value, as would be appreciated by one ofordinary skill in the art encompassed by embodiments of the presentdisclosure. A stated value should therefore be interpreted broadlyenough to encompass values that are at least close enough to the statedvalue to perform a desired function or achieve a desired result. Thestated values include at least the variation to be expected in asuitable manufacturing or production process, and may include valuesthat deviate by less than or equal to 5%, 1%, 0.1%, or 0.01% of a statedvalue.

The present disclosure may be embodied in other specific forms withoutdeparting from its spirit or characteristics. The described embodimentsare to be considered as illustrative and not restrictive. The scope ofthe disclosure is, therefore, indicated by the appended claims ratherthan by the foregoing description. Changes that come within the meaningand range of equivalency of the claims are to be embraced within theirscope.

1. A delivery system for delivering an implantable intravascular deviceto a targeted cardiac valve, the delivery system comprising: a handleassembly; an elongated delivery member coupled to the handle assemblyand extending distally from the handle assembly, the delivery memberhaving a distal end and being configured to detachably couple to anintravascular device at the distal end, the delivery member furtherincluding: an outer sheath having a distal piece configured to house theintravascular device in a pre-deployed configuration; a steeringcomponent configured to curve the delivery member in a compound curvethat enables intravascular delivery of the delivery member to thetargeted cardiac valve; a delivery catheter configured to longitudinallytranslate the intravascular device relative to the outer sheath; and asuture catheter having one or more tethers configured to detachablycouple to the intravascular device, the suture catheter beinglongitudinally translatable relative to the delivery catheter to enableadjustment of tension in the one or more tethers.
 2. The delivery systemof claim 1, wherein the steering component is a steering catheter nestedwithin the outer sheath.
 3. The delivery system of claim 2, wherein thesteering catheter includes a plurality of tension cables andcorresponding tension cable lumen, the tension cables providing forsteering of the steering catheter by adjusting tension in the tensioncables.
 4. The delivery system of claim 3, wherein each tension cablelumen includes a micro coil along at least a distal section of thesteering catheter.
 5. The delivery system of claim 2, wherein thesteering catheter is formed as a hypotube, the hypotube having a cutpattern that increases the flexibility of the hypotube relative to anuncut section of hypotube.
 6. The delivery system of claim 5, whereinthe hypotube includes a distal section, an intermediate section, and aproximal section, the distal section having a cut pattern which enablesa bend radius of about 5 to 15 mm, and wherein the intermediate sectionhas a cut pattern which provides a larger bend radius than of the distalsection.
 7. The delivery system of claim 1, wherein the distal pieceincludes a plurality of microfabricated cuts along at least a proximalsection of the distal piece, the microfabricated cuts being configuredto provide bending in a single plane.
 8. The delivery system of claim 1,wherein the outer sheath includes a coil and a braided sleeve.
 9. Thedelivery system of claim 8, wherein the coil is formed from a coil wirehaving a “D” shaped cross section.
 10. The delivery system of claim 8,wherein the outer sheath further includes a fluid impermeable flexiblepolymer cover disposed over the coil and braided sleeve.
 11. Thedelivery system of claim 1, wherein the distal piece is rotationallydecoupled from the remainder of the outer sheath.
 12. The deliverysystem of claim 1, wherein the outer sheath is coupled to the handleassembly with a swivel connection that enables the outer sheath torotationally swivel relative to the handle assembly.
 13. The deliverysystem of claim 1, wherein the delivery catheter includes a compressioncoil at least at a distal section.
 14. The delivery system of claim 2,wherein the handle assembly is supported by a fixture, the fixtureincluding a plurality of supports which support the outer sheath, asteering catheter handle, a delivery catheter holder, and a suturecatheter holder, the fixture including adjustable controls which enablemovement of components of the delivery member relative to othercomponents of the delivery member.
 15. The delivery system of claim 14,wherein the fixture includes a delivery device adjustor forlongitudinally translating the entire delivery device relative to abase.
 16. The delivery system of claim 14, wherein the fixture includesan outer sheath adjustor for translating the outer sheath relative toother components of the delivery member.
 17. The delivery system ofclaim 14, wherein the fixture includes a deployment adjustor fortranslating the delivery catheter, outer sheath, and suture catheterrelative to the steering catheter.
 18. The delivery system of claim 1,wherein the handle assembly includes a delivery catheter holder, asuture catheter holder, and a suture catheter adjustor, the suturecatheter adjustor being coupled to the delivery catheter holder, and thesuture catheter holder including threads which engage with correspondingthreads of the suture catheter adjustor such that rotation of the suturecatheter adjustor translates the suture catheter holder relative to thedelivery catheter holder.
 19. A delivery system for intravascularlydelivering an implantable intravascular device to the mitral annulus,the delivery system comprising: an elongated delivery member coupled tothe handle assembly and extending distally from the handle assembly, thedelivery member having a distal end and being configured to detachablycouple to an intravascular device at the distal end, the delivery memberfurther including: an outer sheath having a distal piece configured toconstrain the intravascular device in a pre-deployed configuration; asteering catheter configured to curve the delivery member in a compoundcurve that enables intravascular delivery of the delivery member to thetargeted cardiac valve; a delivery catheter configured to longitudinallytranslate the intravascular device relative to the outer sheath; asuture catheter having one or more tethers configured to detachablycouple to a proximal section of the intravascular device, the suturecatheter being longitudinally translatable relative to the deliverycatheter to enable adjustment of tension in the one or more tethers; anda guidewire tube extending through the delivery member and through thedistal piece to an attached distal tip, the distal tip being configuredto connect to or seat against a distal side of the distal piece; and ahandle assembly, the handle assembly including: an outer sheath holdercoupled to the outer sheath at the proximal end of the outer sheath; asteering catheter handle disposed proximal of the outer sheath holder, aproximal end of the steering catheter being coupled to the steeringcatheter handle and the steering catheter extending distally therefrominto the outer sheath; a delivery catheter handle disposed proximal ofthe steering catheter handle, a proximal end of the delivery catheterbeing coupled to the delivery catheter handle and the delivery catheterextending distally therefrom into the steering catheter; and a suturecatheter handle disposed proximal of the delivery catheter handle, aproximal end of the suture catheter being coupled to the delivery suturecatheter handle and extending distally therefrom into the deliverycatheter.
 20. A delivery system for intravascularly delivering animplantable intravascular device to the mitral annulus, the deliverysystem comprising: an elongated delivery member coupled to the handleassembly and extending distally from the handle assembly, the deliverymember having a distal end and being configured to detachably couple toan intravascular device at the distal end, the delivery member furtherincluding: an outer sheath having a distal piece configured to hold theintravascular device in a pre-deployed configuration; a steeringcatheter configured to curve the delivery member in a compound curvethat enables intravascular delivery of the delivery member to thetargeted cardiac valve; a delivery catheter configured to longitudinallytranslate the intravascular device relative to the outer sheath; asuture catheter having one or more tethers configured to detachablycouple to the intravascular device, the suture catheter beinglongitudinally translatable relative to the delivery catheter to enableadjustment of tension in the one or more tethers; and a guidewire tubeextending through the delivery member and through the distal piece to anattached distal tip, the distal tip being configured to connect to orseat against a distal side of the distal piece; and a handle assembly,the handle assembly including an outer sheath holder, a steeringcatheter handle, a delivery catheter holder, and a suture catheterholder; and a fixture configured to support the handle assembly, thefixture including: a delivery device adjustor for longitudinallytranslating the entire delivery device relative to a base; an outersheath adjustor for translating the outer sheath relative to othercomponents of the delivery member; and a deployment adjustor fortranslating the delivery catheter, outer sheath, and suture catheterrelative to the steering catheter.